Measuring and reporting website data has become an important element of digital marketing. Here, we look at some of the common metrics and explain the pitfalls to avoid when drawing conclusions from them.

Visitors vs returners

An individual navigating to your site for the first time is called a new visitor. Returning users or ‘returns’ are those who have previously visited your site and have come back. Tools such as Google Analytics can identify return users through cookies or authentication.

An increase in new visitors can indicate your audience is growing, maybe because other marketing channels are driving people to your website. If you have a high number of returns, or this metric is trending upwards, it suggests you have a loyal user base that values the content on your site.

Sessions vs duration

A session is a group of actions taken on your website by a single user in one sitting, including browsing pages, watching videos or making an online purchase. A session ends when the user navigates away, or after 30 minutes of inactivity. The terms ‘visit’ and ‘session’ are often used interchangeably.

Page duration is the time spent by a visitor on a single webpage. Comparing how long users spend on different web pages can guide improvements to your site layout. The ‘session duration’ metric is also useful because it describes how long single users remain on your site as a whole. A higher session duration rate indicates your website is more engaging and ‘sticky’.

Bounce rates

The ‘bounce rate’ shows the percentage of visitors who leave your website after viewing only one page. A high or rising bounce rate may mean your site is unattractive or off-putting. It’s worth remembering that a user may carry out a successful interaction using only one page, especially if they then make an offline purchase. However, analytics tools still consider this to be a bounce.

Impressions vs engagement

Impressions are the number of times a piece of content – for example an advert – is requested from the server hosting the site. In layman’s terms, it’s a rough gauge of how many times an advert or piece of content has been viewed.

A drawback with measuring impressions is that the data can be easily skewed. A single visitor returning to the same content multiple times, or a ‘robot’ programme artificially triggering the counter can lead to a misleadingly high impression count.

Engagement is a more general term used to describe the degree to which users value and interact with your website. It is usually worked out as a function of how many links a visitor clicked, how long they spent on the site, and how often they return.

Conversions vs KPIs

A ‘conversion’ is the successful completion of a sequence of actions by a website visitor that meet a business’s goals or marketing objectives. The nature of the conversion depends on the focus of your marketing campaign and is typically a measurable action, such as an online purchase, or the signing of an online petition.

Key performance indicators are unique to each company, because they relate to how well your online activity is supporting your marketing objectives. For a company aiming to maximise sales, measuring the conversion rate would be a sensible KPI. You might be interested in other metrics, such as number of unique page visits, but these will not be your KPIs.


Cost-per-acquisition is a powerful metric that helps marketers demonstrate whether campaigns are effective in financial terms. CPA measures the average cost of acquiring one new paying customer, calculated by dividing the cost of the marketing campaign by the number of conversions.


None of the metrics outlined here tells the full story by itself. Only by combining data can you piece together a complete picture and draw valid conclusions about your customers and website users.

It’s also important to remember the golden rule of web analytics: establish your marketing goals and business objectives before diving into the data. Without knowing your destination, you can’t begin to measure whether you’re getting there.

Do you have regular reports from Google Analytics but no real idea what they mean? Sign up to our Google Analytics course and learn what matters most in this powerful reporting tool.

Source: James Richards / Freelance Journalist